Article: Watershape University: Filling a Void

Swimming pools are so commonplace; it’s easy to take them for granted. When we step back and consider, in specific terms, what the industry is about and what it does, however, we find a profound and even surprising need for education as well as licensing and certification.

It’s a big industry. The U.S. boasts 10.7 million swimming pools, both commercial and residential. Each on is different and serves the needs of people of all ages, incomes, religions, races, and cultural origins. Pools are a place where humanity comes together for essentially the same purpose - to enjoy being on, near, or under the water.

Pools are not only popular and plentiful; they are also complex. A lot can go wrong with a pool that isn’t built correctly - from structural failures to aesthetic imperfections to inefficient or unreliable operation; therefore, a swimming pool requires the work of professionals during design, engineering, construction, and service. The public deserves a means by which to decide if the investment they’ve made in their new pool is not only soundly designed and esthetically pleasing, but robustly constructed for the long lifespan concrete pools are capable of.

Answering the call

All of that is why Watershape University (WU) exists. It is our objective to equip industry professionals with the knowledge they need to meet consumer demands - today and into the future.

Ever since the formation of WU in Fall 2019, curious minds have rightfully asked us what this organization is all about, what our goals are, and the means we’ve been using to achieve those needs.

Ultimately, many interested parties want to know how we are working to fill the education void and improve the shotcrete knowledge that exists within the world of pools, spas, and other forms of recreational and/or decorative bodies of water.

What’s a watershape?

The creators of Watershapes magazine coined the term before the magazine debuted back in February 1999. It’s essentially shorthand for all forms of recreational and decorative water including pools, spas, fountains, ponds, streams, lazy rivers, waterfalls, interactive water features, water gardens, natural bodies of water, and even birdbaths.

The magazine spearheaded an educational movement that sought to redefine water in the landscape as an architectural design element and an art form - a campaign that continues to this day.

What is Watershape university?

Watershape University (WU) is a leading professional authority on quality live and online instruction for business, design, engineering, construction, repair, restoration, and service. We serve students of all levels in the pool, spa, aquatics, and outdoor living sectors. Although recently founded by David J. Peterson and me, WU encompasses decades of teaching and practice among staff, faculty, and volunteers engaged in its educational and credentialing programs.

Why do we exist?

WU was created to ensure long-term prosperity within watershaping industries by supporting the growth of an educated, professional workforce. We also exist to raise awareness of the benefits of an aquatic lifestyle.

Our efforts first grew out of the founder’s shared desire for staff training within their own companies. While other sources were either too expensive or not technical - or design- oriented enough, the WU curriculum exists to fill those voids.

What do we strive to accomplish?

We are working to create an educated class of individuals and companies dedicated to elevating the professionalism of the watershaping industries while also inspiring everyone to experience the joy and benefits of recreational and decorative water.

What means do we use to accomplish those goals?

WU’s curricula are based on third-party (IACET) accreditation, providing a credentialed path for career advancement. We are financially supported by student fees as well as support from watershape manufacturers and suppliers.

WU has aligned with ASA specifically in the area of education for quality shotcrete placement in pools. Helping both pool builders and self-performing shotcrete contractors recognize the inherent requirements for quality shotcrete placement and the resulting impact on the servicability and durability of the watershapes they are building is a joint effort. Working together, WU leverages the experience of ASA members to broaden shotcrete knowledge across the pool marketplace. ASA members participate in many internationally recognized organizations that develop codes and standards, and together, we bring the shotcrete-specific knowledge to the pool industry through institutions like WU.

WU provides coaching and outreach through the International Watershape Institute, a group of our most accomplished instructors and students. Finally, we support the Live Blue Foundation, an affiliated organization established to provide grants to organizations putting what we call the “Blue Mind” concept into action. Blue Mind is the mildly meditative state people fall into when they are near, in, under, or on water. Blue Mind illustrate ways people can use water to improve their overall well-being.

What values and benefits sustain our efforts?

As both idealists and realists, we believe that principled leadership, honesty, integrity, a supportive culture, compassion, gratitude, and altruism will inevitable result in personal growth and professional gain for the entire industry.

Who benefits from WU?

Many stakeholders benefit from WU, including our credentialed students, as well as their companies, employees, and subcontractors; faculty and coaches; associate corporations, colleagues, and partners; peers and the entire professional water shaping community; and owners and consumers.

To what end?

It’s been said that swimming pools are the gateway to the world of water, and Waterscape University is considered the educational authority on how best to design, build, service and sell waterscapes.

how do we define our mission?

Our mission centers around getting people near, in, on, or under water for life; it also recognizes pools as the gateway to water and accredited education as the means to design, build, service, and sell pools according to best practices.

WU encourages personal development through membership in the elite International Watershape Institute, which provides principled leadership, a supportive culture, and altruism to benefit the industry and our society.

Article: Why We Need a Design Code for Concrete Pools

The swimming pool design and construction industry is not highly regulated, and in some cases, it is simply not regulated. Some states and municipalities require licensed professional engineers to design all pools. Some jurisdictions require only commercial pools to have a set of plans and specifications that are produced and sealed by a licensed design engineer. Unfortunately, they have no requirements for a licensed engineer to design a residential pool.

Residential pools can far exceed $100,000 in cost depending on the complexity. They have pumping and piping systems, drains, sumps filters, electrical, and water treatment equipment. Today’s pools are no longer just rectangular concrete swimming ponds in the backyard (Fig. 1).

Fig. 1: Partially buried, embedded window, infinity edge residential pool. Not just a basic backyard swimming hole (Photo courtesy of Drakeley Pools).

Thus, though the industry is large, the pool designers have free rein to do whatever. Many are not licensed professional engineers and have no requirements to seal a set of drawings or specifications. Some designers sell typical pool designs that take no account of the local site conditions or environmental exposures. The pool industry is totally unregulated in many states. Where some states do require designs which are signed and sealed, they still rely on the engineer’s various degrees of experience or selection preferences from existing codes that do not directly relate to pool design and construction. This isn't necessarily the fault of the designer as there is not a well-established industry standard to set minimum requirements in the pool industry.

ASA has established a set of position statements for the pool industry. They address issues including Compressive Strength Values of Pool Shotcrete, Shotcrete Terminology, Sustainability of Shotcrete in the Pool Industry, Watertight Shotcrete for Swimming Pools, Monolithic Shotcrete for Swimming Pools (No Cold Joints), Forming and Substrates in Pool Shotcrete, and Curing of Shotcrete for Swimming Pools.

The ASA position statements are valuable to convey the expectations of good practices in the pool marketplace. Perhaps they will even start to set an industry standard. But these are short, non-mandatory documents meant to provide guidance. ASA is not a standards-developing organization (SDO) like ACI or ASTM.

A code is a mandatory language document that provides minimum requirements for design and some construction aspects of the structure within its scope. For example, when engineers design buildings, it is clear they use ACI 318 Building Code Requirements for Structural Concrete and Commentary. Proper use of ACI 318 is taught throughout their college education and widely used in the industry in many parts of the world.

So, where are we in the pool industry? The current International Swimming Pool and Spa Code (ISPS) has a minimal basis for concrete pool design. Here are the current ISPSC provisions for structural design:

802.1 Materials of components and accessories.

“The materials of components and accessories used for permanent inground residential swimming pools shall be suitable for the environment in which they are installed. The materials shall be capable of fulfilling the design, installation, and the intended use requirements in the International Residential Code."

802.2 Structural design.

“The structural design and materials shall be in accordance with the International Residential Code."

SECTION 803

CONSTRUCTION TOLERANCES

803.1 Construction tolerances.

"The construction tolerance for dimensions for the overall length, width, and depth of the pool shall be + 3 inches (76 mm). The construction tolerance for all other dimensions shall be + 2 inches (51 mm), unless otherwise specified by the design engineer."

These three short sections don't even fill a full page. That's it for the ISPSC on concrete pool structural design. The requirement is to just use the International Residential Code (IRC) for structural design.

Let's turn to the Introduction of the International Residen-tial Code (IRC) where we find:

"The International Residential Code (IRC) establishes minimum requirements for one- and two-family dwellings and townhouses using prescriptive provisions. It is founded on broad-based principles that make possible the use of new materials and new building designs."

But what chapter of the IRC addresses pool structural design? Maybe Chapter 6, Walls? Looking at R608.2 in Chapter 6, it appears that likely pools would only be covered by the following provision: "Buildings that are not within the scope of this section shall be designed in accordance with PCA 100 or ACI 318." There is Chapter 42, Swimming Pools, of the IRC, but it only covers the requirements for protection of occupants from electrical shock.

Both ACI 350, Code Requirements for Environmental Engineering Concrete Structures and Commentary, and ACI 318 are comprehensive concrete design codes accepted in jurisdictions around the world. ACI 350 is based on the ACI 318 Code, but it includes specific enhancements for designing liquid-tight concrete structures that are routinely exposed to water. ACI 318 is written to address concrete buildings. In comparison to ISPSC provisions for concrete pool structural design at less than one page, ACI 350-20 is 545 pages.

Swimming pools are constantly filled with water and hopefully intended to be watertight. Thus, of the two codes, ACI 350 is the more appropriate code. The ACI 350 Code has design provisions intended to limit crack widths and provide long-term serviceability and durability for the water-containing structure. Many designers of large commercial pools use ACI 350 for their designs. However, there has been much discussion in the pool industry that ACI 350 is not specifically geared towards pools and has too high a requirement for some on the various industry committees.

But in thinking about the issue - how do you design a pool for long life and watertightness? — ACl 318 isn't appropriate because it doesn't deal with crack control, watertight-ness, or continuous exposure to water with wetting and drying. On the other hand, ACI 350 has a massive scope to cover all types of liquid-containing structures in water, wastewater, and industrial process applications. There are many provisions that have no direct application in pools (like shear walls, roofs, beams, torsion members, prestressing, precast, etc). But concrete pools have become increasingly complex (Fig. 2), and designers need much more specific guidance. In evaluating the currently available codes, it is clear we need a pool-specific ACI Code.

Fig 2: Complex reinforcing with integral spa and embedded piping. Not a simple design or construction (Photo courtesy of Drakeley Pools).

Recognizing the need for specific design guidance in the pool marketplace, I proposed to the ACI Technical Activities Committee (TAC) that they establish a new technical committee charged with developing a code specifically for pools. And they did by establishing the ACI 322 Concrete Pool and Waterscape Code committee in late 2021.

The committee has had four in-person meetings since its inception. We are currently looking at a subset of the ACI 350-20 Code Provisions dealing with structural issues but gearing it towards just the structural requirements needed for the pool industry. The ACI 322 committee is producing the new 322 Code in a member-based format as introduced in ACI 318-14. Unfortunately, ACI 350-20 is based on the earlier format in ACI 318-11, so we are expecting quite a bit of work to reorganize the content.

One of our first challenges was creating a list of what we, as a group of experienced pool designers, needed to cover in the code. The following list of topics we discussed at the committee shows how comprehensive we expect the code to be. (Sidebar left.)

Where ACI 350 and ACI 318 are very broad in scope and fine for all types of concrete tanks and buildings, the design requirements are quite detailed and somewhat onerous if one is designing more limited pools and watershapes. Thus, the new ACI 322 Code for Pools and Watershapes committee was approved by ACI.

It will take us several years to complete the first version of the ACI 322 Code. Our goal, once it is complete, is to have the ISPSC adopt the ACI 322 Code for concrete pool design, as the International Building Code (IBC) adopted AC 318 for buildings.

Our ACI 322 committee membership is still open. If you have expertise in pool design or construction and would like to help develop the design standard for the pool industry, you can apply online at www.concrete.org/committees/joinacommittee.aspx

The current design methodology for the concrete pool industry is kind of like the "Wild West." It's time to tame it!

Article: Robust Contentment

Fig. 1: A swimming pool can never visually compete with the ocean. For this project, the elegant pool design serves as a perfect complement to the spectacular setting.

This beautiful project, nestled on the Connecticut shores of the Long Island Sound, required a careful balance of robust construction and design, and careful adherence to the environmental codes protecting the adjacent oceanic rock formations and biologically sensitive tide pools. “It was a steep challenge,” explains Bill Drakeley, but he and his company welcomed the opportunity.

This project started with a spectacular setting. It’s located in Connecticut in an area known as the Gulf Coast on Long Island Sound. It’s in an exclusive, private community where people both enjoy the outdoor lifestyle but are also mostly very private. It’s not a place where they have neighborhood block parties.

These particular clients are exceedingly wealthy, making a fortune in finance. They have an extremely low profile and treasure their contented lifestyle. They are also thankful for their success, and are very athletic, healthy people who use swimming as part of their fitness regimen.

The pool we created for their home was designed to reflect and serve all of those qualities. It’s both beautiful, fits neatly with the setting, and is also built for swimming.

Fig. 2: Aerial view showcasing the unique five-sided shape, the beautiful landscaping, and the oceanic rock formations that make this pool both aesthetically appealing and environmentally conscious.

Fig. 3: Executing the precise edge detail required zero tolerance construction and dogged adherence to all applicable workmanship standards.

Across the waters

The property is right on the water in an area that features protected coastal rock formations and tide pools. It’s an enormous property that includes a number of small satellite islands just off shore. Even working at the so-called high-end of the market, it’s rare to work on a property with its own archipelago.

The pool was being build as part of a complete property renovation. It’s big and is basically a rectangle with an angled cut out on the deep end that makes it technically a five-sided polygon. It’s 60-ft (18 m) long, 20 ft (6 m) on the shallow end, and 16 ft (5 m) at the narrow end, which is 9 ft (2.7 m) deep.

From the start, we were told the pool was built for swimming; the clients and their grown children are all athletic and regular swimmers. They’ve been all over the world scuba diving, sailing, deep-sea fishing, and very much living an adventurous, aquatic lifestyle. They needed a pool that was not dainty, so that’s what we gave them.

The interior is designed with narrow, 2 ft (0.6 m) steps and a long bench that runs the length of the pool to take advantage of the view while, at the same time, leaving as much room for swimming as possible.

It also has to be beautiful. It’s an all-perimeter overflow designed by Janice Parker Landscape Architects based in nearby Greenwich, CT. She’s a truly gifted designer who pays attention to both the big picture and the fine details; she is always working to find the best solution for the project parameters in play.

In this case, the aesthetic is relatively simplistic and based on the idea that you don’t visually want to compete with the natural setting; instead, the aesthetic forges a visual connection between the landscape and the view of the ocean. Hence, the edge detail that raises the reflective surface of the water to grade, creating a powerful yet subtle visual transition. It looks great from all angles.

Edge on a ledge

Parker brought us into the project and asked us to submit a bid to the general contractor who builds super-high-end residential projects. When we were introduced to the project team and the owners, we immediately started talking about some of the specific challenges involved with building the pool so close to the water.

Fig. 4: Working so close to the shore can create challenges when it comes to the needed substructure and dealing with ground water or sandy soil conditions.

The pool abuts a rock ledge that’s part of the coastline’s natural geology, which includes beautiful and environmentally sensitive tide pools. Additionally, we had to work around a pine tree immediately adjacent to the pool that is growing up through a rock outcropping, which is the reason for the angled portion of the pool shape.

Working against what amounts to a natural seawall, there was also water constantly moving into the ground, so we had to run a dewatering system throughout the entire course of the project. In that setting, we would build a big pool with a 360 degree perimeter overflow detail and surge tanks - all without disturbing so much as a single snail.

Fig. 5: That was not the situation here. The solid-rock shoreline in this area served as the form for the pool structure, an advantage that simplified the process.

The pool structure itself is carved out of solid rock, so there was no need for piles, grade beams, or any kind of elaborate foundation. We made sure the rock was stable and drainable, which it was, but we also installed hydrostatic relief valves throughout the pool. The excavation required some heavy-duty jackhammering, but it was done in such a way to leave the natural rock untouched.

Fig. 6: So often, the true art and craft of the construction resides in details that will go unseen once complete. The near-perfect formwork on this project is a prime example.

Drakeley Pools was chosen largely because of our experience in large, complex projects - both residential and commercial. We’re good at construction details and also at explaining to building departments, health departments, and city officials how a pool needs to work that won’t work.

surge elevation

Fig. 7: It’s a basic consideration, but property elevating the steel above the ground is critical for structural integrity. Simple details matter. As is true of all-perimeter overflow systems, the forming, reinforcing steel, and shotcrete had to be installed to the highest possible standards and low tolerances. Suffice it say, this was not a job for a novice builder.

Because of the environmental regulations, we cannot locate pool equipment in the storm surge. Our circulation system had to be designed with surge tanks below grade that circulate to an equipment pad that’s 60 ft away and 15 ft (4.6 m) above grade in a secondary outbuilding. Specifically, FEMA regulations prohibit filtration systems at sea level.

The code language in FEMA 4 states that “where appropriate” all mechanical systems need to be above the storm surge line. In this case, working with a gravity edge-flow system, there is no way to pump the water uphill with pumps at a higher elevation. I pounded on that concept and explained that, in this case, the requirement for all equipment to be elevated was decidedly not feasible. It simply wouldn’t work. Fortunately, that argument was convincing enough for them to approve a variance.

The plumbing comes off the overflow gutter manifold and in suction outlets on the bench inside the pool. It flows to a surge tank beneath the garage of the main house where we have four pumps pulling from a tank and pushing the water uphill.

From there, it is pumped up to the second building where the filters, heater, and treatment systems are located. The flow is divided between the edge overflow, the filtration and heating systems, and a third that feeds the ozone/chemical treatment system.

The return flows back to the pool via the same path, back down the hill, around the surge tank, and back to a series of flow returns in the pool floor. It’s a tricky hydraulic set up that we engineered in-house.

It took quite bit of convincing, lobbying, and repetition, but in the end, the powers that be approved the plan and we were able to go forward.

And through it all, the precious pine tree still stands and commands the view, and the inhabitants of the tide pools didn’t even know we were there and remain as content as can be.

PROFILE: Watershape University

Watershape University: Defining Aquatic Excellence at Every Turn

Watershape University (WU) is a leading provider of quality instruction -- live and online -- targeting the business of watershaping with design, engineering, and construction programs for students of all levels in the pool, spa, aquatics, and outdoor living sectors. WU supports and promotes the use of recreational and decorative water through accredited education and fosters a greater understanding of the benefits and value of aquatic activities and lifestyle.

Although founded in August 2019 by David J. Peterson and William T. Drakeley, WU is defined by decades of teaching and professional practice among staff, faculty, and volunteers engaged in its educational and credentialing programs. WU encourages personal development through membership in the elite International Watershape Institute (IWI), providing principled leadership, a supportive culture and altruism to benefit the industry and society.

Our multi-pronged approach includes third-party accredited education designed to provide a credentialed path for career advancement through WU; financial support from manufacturers/suppliers through corporate engagement; coaching and outreach through the IWI.

WU acquired WaterShapes.com (formerly WaterShapes Magazine) in Spring 2020 as a trusted, digital resource for the industry, professional community, and consumers of all things aquatic. WU has also established on ongoing strategic alliance with Wallace “J” Nichols, author of the best-selling book “Blue Mind.” With J, WU established the Live Blue Foundation, a non-profit organization devoted to “getting people near, in, on and under water – for life.”

We believe that principled leadership, honesty and integrity, a supportive culture, and altruism will result in personal growth and professional gain for the entire industry and consuming public. We mean to see pools and other types of watershapes recognized as the gateway to the world of water, and WU considered the leading educational authority on how best to design, build, service and sell manmade bodies of water.

The work we do at WU has widespread benefits. Our constituents include: our credentialed students; their companies, employees and subcontractors; our faculty and coaches; corporations engaged as WU associates, colleagues and partners; the entire professional watershapes community; consumers, and all of humankind.

WU is founded on the premise that an educated “team” of professionals is the best setting for collective and individual success. To borrow an iconic phrase “of the people, by the people, for the people” – that is WU. We are an ever-growing, and evergreen TEAM of individuals and companies working together to ensure the long-term prosperity of the aquatics industry through an educated workforce and an educated world on the benefits of an aquatic lifestyle.

Principled universities long survive their founders. That is the expectation with WU – a living and breathing entity that will thrive long into the future, based on values and principles that have always and will forever endure.

WU is devoted to promulgating the highest possible standards for design, engineering and construction, including those maintained and promoted by ASA for proper and reliable mixing and placement of shotcrete.

To view the full profile in Shotcrete Magazine, click here.

ARTICLE: Failures of Trust

Engineers carry an almost sacred trust, with watershapers relying on them to design structures and systems that are reliable, science-based and code-compliant. When that trust is broken, the consumer’s investment is at risk -- as is the watershape builder’s reputation.

Engineers are highly trusted. In a recent Gallup poll asking which professions are the most trusted, nurses were number one and engineers came in second. Engineers placed above medical doctors, police, psychiatrists and clergy. Not surprisingly, used-car salesmen and members of Congress were at the bottom of the polls!

That high level of public trust begs the question of whether or not engineers truly warrant such rock-solid credibility? Engineers are not all the same and certainly when considering the profession, most are trustworthy, practicing ethically and responsibly. However, there are some that most assuredly are not. Unfortunately, a clear and compelling example of less than responsible engineering can be found here in the pool industry.

When you obtain a set of plans from a consulting engineer – a structural design, for example – you have every right to believe that their calculations, specifications and plans are properly prepared and correct for the project at hand. In most cases, that trust is well-founded; but there are some glaring exceptions.

You run into problems with what we call “mail order” or “off the shelf” plans developed and sold by a few engineering firms. By packaging generic plans, these firms enhance their profits while dumbing down their specifications and allow builders to cut corners.

Some people refer to these as “standard plans,” which is a euphemism and misnomer. No two pools are exactly alike. The soils are never exactly the same, nor the property, the environmental conditions, and certainly not the homeowners. Therefore, there really is no such thing as a standard plan. We believe engineers that market plans as such are not meeting the standards required of true professional engineers.

PERPETUATING MYTHS

The unfortunate fact is, many pool builders will use an engineer’s generic design, plans and specifications if they think it will lower the cost of the pool, when compared to more rigorously engineered plans designed for a specific pool project. Some builders will ask, why should I use #4 (#13M) reinforcing bars when this engineer says I can get away #3 (#10M)? Mail-order engineers give them the answer they want.

In other words, not all engineers should be trusted. Some of the lowered standards you see in mail-order plans do, in point of verifiable fact, lead to failures or produce a final pool structure that is much less durable. The fact that the engineer’s plans and resulting structure was not engineered for the specific conditions of a particular site only becomes known, all too often, in the discovery phase of an expensive and time-consuming lawsuit.

The ugly truth is, there are engineers who will lie to you because they’re more concerned with their bottom line than they are with their responsibility to prepare proper designs as expressed in the integrity of their plans. They may ignore some ethical codes while seeking profits.

The good news is it’s often easy to spot an unscrupulous engineer in the pool construction industry if you know what to look for. Usually, the corners they cut will be obvious in their project deliverables.

In our industry the biggest area of deception is concrete and reinforcement. They cut corners in the compressive strength and permeability of concrete, cover over the embedded reinforcing steel, the size and spacing of reinforcing steel and even the thickness of the concrete. They attempt to get away with it by using clever language that’s meant to confuse builders and authorities having jurisdiction.

One of the arguments, for example, is that it’s okay for concrete to be permeable, because that’s the plasterer’s job. Builders don’t have to worry about water permeating the concrete shell because the plaster is there to stop it. Well, that’s just not true. A properly designed and constructed concrete pool shell should be functionally watertight.

Click here to read the full article featured in Shotcrete Magazine.

ARTICLE: Hot Weather Shotcrete

Placing shotcrete in hot weather can be a risky proposition if you don’t follow basic guidelines. Success under these conditions, calls for controlling concrete temperature and mixture design while also managing details of the installation and curing processes.

The summer is always busy, but that may be a huge understatement this year. The country is coming back to life with consumers very aware of their personal space and wanting to do more with it – which, often times means adding watershapes.

As a result, the heightened demand for our pool industry’s products will likely lead to all sorts of logistical and supply issues. The availability of concrete may well be one of those critical issues. Ready-mix suppliers have informed me that during this forced downtime, many homeowners, do-it-yourselfers, are taking on their own concrete work. Suppliers caution that when the contractors fully come back online during the summer, there could be delays in product supply and even shortages of ready-mix delivery trucks. To varying degrees, it’s often true that hot weather and elevated temperatures drive up demand.

Especially with the current extraordinary circumstances, the first step in hot-weather concrete work, whether you’re doing wet-mix or dry-mix shotcrete, is you need to communicate with your concrete material suppliers and place orders well in advance. That’s the only way you’ll know what to expect for availability and delivery, so you can schedule accordingly and in turn let the client know what to expect.

Beyond that basic caveat, there are specific measures and conditions required whenever you’re placing concrete in hot weather. Shotcrete placement in hot weather requires temperature control, environmental control, and jobsite control.

ENVIRONMENTAL CONDITIONS

I currently serve as Chair of American Concrete Institute’s (ACI) 506-H Pool Shotcrete Committee. We are writing guidelines for the shotcrete placement process, as it pertains to both wet- or dry-mix for pools. In the hot weather shotcrete section, we refer to the existing hot weather concreting documents from ACI 305, which define acceptable concrete temperatures and procedures.

According to the ACI 506 pool shotcrete document, you should always keep concrete as cool as possible. You should not apply shotcrete when ambient temperatures are over 95°F (35°C), unless special precautions are taken. The precautions should be reviewed by the pool designer or other experienced engineer. You can cool the concrete by using cold water to mix it, misting systems, wetting blankets, and shade. Each of these options slow down evaporation and help reduce the potential for early age plastic shrinkage cracking on the surface of the concrete.

Considering what’s happening in the fresh concrete matrix helps explain why these measures are necessary. When you mix water with portland cement hydration occurs. The cement hydration produces changes in the cement particles that lead to strengthening as the particles interlock. The hydration process leads to a volumetric change in the concrete, as well as additional heat from the chemical reaction.

When you’re already working in warm conditions, you can easily wind up generating too much heat if you’re not taking measures to cool down the environmental temperatures and the concrete itself. If temperature of reinforcement, embedments, or forms is greater than 120°F (49°C), use a fine mist of water to moisten and cool hot surfaces. Remove standing water before shotcrete placement.

Yes, it is possible to successfully place shotcrete in temperatures over 105°F (41°C) or even higher – consider Arizona and Nevada. But you must take recommended precautions. Do everything you can to avoid the heat of the day by working in the morning, if possible. You may also consider erecting a shade structure to keep the concrete, forms and reinforcing out of direct sunlight.

To read the full article featured in Shotcrete Magazine, click here.

ARTICLE: Transparent Ingenuity

Working in the custom swimming pool market requires a keen understanding of how shotcrete can be adapted to complex and challenging structures. The work necessitates creativity on one hand and adherence to ACI and ASA standards and practices on the other. It means being inventive and disciplined at the same time.

The Sherwood water shape project is something special. It’s one of the more creative and challenging residential swimming pool environments we’ve ever created and I’ve been humbled by the recognition it’s received. Looking back, I now see it as a prime example of the importance of understanding how all the phases of pool building fit together and support each other. There is a healthy list of takeaways from this challenging and award winning project. Topping that list stands the importance of understanding shotcrete and the techniques used to place it.

IN SITU

Located on the Connecticut coast overlooking Long Island Sound, the water feature drew its contemporary design from the architecture of the new house, a modern version of the old coastal mansions once built and adorned by the Rockefellers, Morgans, and Vanderbilts. The house and surrounding architecture and landscape architecture incorporate a contemporary yet strict linear version of hillside old-world construction. It’s a spectacular property that warranted an equally eye-catching water shape design.

The house and all its features, including the pool, blend into the modernist property overlooking the ocean. The pool is a reflection of the architecture and the spectacular setting. It’s a three-tiered pool, spa, vanishing edge, slot overflow and acrylic panel design with a German Grando cover that rolls out from an automatic shotcrete floor vault and sits onto a shotcrete ledge along both long walls of the pool.

All of this is set on a dramatic slope – there’s a 20-ft (6.1 m) drop from the top of the pool area to the bottom of the equipment vault. The soil conditions vary wildly on the property due to the site’s many uses dating back to colonial days, meaning the structural design relied heavily on soils analysis and geotechnical engineering.

To effectively execute a project of this complexity, every step in the process is aimed at setting the stage for the next, from the excavation up to the finish materials. The topography and spacing of construction required marrying proven shotcrete methodology into and on top of, a form-and-pour filter vault and supporting lower wall foundation.

The structure’s footprint and position were first established with rock and ledge removal down to a workable and competent substrate. We then cast the supporting foundational walls, footings, and locking mechanisms into the steep vertical slope of the pool area.

Click here to read the full article featured in Shotcrete Magazine.

ARTICLE: Acrylic Pool Walls and Windows

Add a sleek, modern look to your poolscape with acrylic pool walls.

Pool builders and homeowners constantly find new ways to set their pools apart from others—and one of the most eye-catching and attractive features to make a pool stand out are clear acrylic pool walls.

“It creates depth, it adds another dimension,” says Paul O. Gardner, vice president of engineering, quality & safety at Reynolds Polymer. “It takes the pool experience to another level.”

“An acrylic viewing window adds a dramatic effect to the simplest of designs,” says Jason Jovaag, general manager of Aquatic Glazing International. Acrylic windows stand out day or night, “whether it’s the ambient sunlight casting rays into the pool,” says Jovaag, “or LED lights illuminating the poolscape at night.”

The experts recommend placing your acrylic wall at the focus point of the pool—they’re common beside a sunken fire pit lounge, or at a negative edge. “It ends up being like an open campfire on a summers night,” says Gardner. “You can’t stop looking at it.” 

The most important thing to note: the structures aren’t easy to build. “These take serious engineering,” says Bill Drakeley, principle and founder of Drakeley Pool Company. “The test of a quality installation is how does it weather over one season, two seasons, five seasons,” he says. “The hard part is making it continuously perform, and making it sustainable year after year.”

Acrylic panels are easiest to add to pools in warmer climates with little temperature variation. While acrylic panels aren’t for every homeowner, Gardner says that “with proper engineering and consideration of the environment, there are solutions for most conditions.”

Click here to read the full article featured in Luxury Pools + Outdoor Living.

ARTICLE: How to Apply Shotcrete

Bill Drakeley, principal of Drakeley Pool Company, is a well-respected expert witness and educator on the use of shotcrete in mines, tunnels, and of course, swimming pools and other water-holding stuctures. 

In his article in AQUA magazine "How to Apply Shotcrete," Bill reiterates the message he has long promoted: quality material applied using excellent technique equals a strong and durable structure. Anything less is a disservice to the client and to the construction industry.